diff --git a/erpnext/hr/doctype/shift_type/shift_type.py b/erpnext/hr/doctype/shift_type/shift_type.py
index 17bca60..27d368c 100644
--- a/erpnext/hr/doctype/shift_type/shift_type.py
+++ b/erpnext/hr/doctype/shift_type/shift_type.py
@@ -3,21 +3,23 @@
 
 
 import itertools
-from datetime import timedelta
+from datetime import datetime, timedelta
 
 import frappe
 from frappe.model.document import Document
-from frappe.utils import cint, get_datetime, getdate
+from frappe.utils import cint, get_datetime, get_time, getdate
 
+from erpnext.buying.doctype.supplier_scorecard.supplier_scorecard import daterange
 from erpnext.hr.doctype.attendance.attendance import mark_attendance
 from erpnext.hr.doctype.employee.employee import get_holiday_list_for_employee
 from erpnext.hr.doctype.employee_checkin.employee_checkin import (
 	calculate_working_hours,
 	mark_attendance_and_link_log,
 )
+from erpnext.hr.doctype.holiday_list.holiday_list import is_holiday
 from erpnext.hr.doctype.shift_assignment.shift_assignment import (
-	get_actual_start_end_datetime_of_shift,
 	get_employee_shift,
+	get_shift_details
 )
 
 
@@ -90,46 +92,60 @@
 		"""Marks Absents for the given employee on working days in this shift which have no attendance marked.
 		The Absent is marked starting from 'process_attendance_after' or employee creation date.
 		"""
-		date_of_joining, relieving_date, employee_creation = frappe.db.get_value(
-			"Employee", employee, ["date_of_joining", "relieving_date", "creation"]
-		)
-		if not date_of_joining:
-			date_of_joining = employee_creation.date()
-		start_date = max(getdate(self.process_attendance_after), date_of_joining)
-		actual_shift_datetime = get_actual_start_end_datetime_of_shift(employee, get_datetime(self.last_sync_of_checkin), True)
-		last_shift_time = actual_shift_datetime.actual_start if actual_shift_datetime else get_datetime(self.last_sync_of_checkin)
-		prev_shift = get_employee_shift(employee, last_shift_time - timedelta(days=1), True, 'reverse')
-		if prev_shift:
-			end_date = (
-				min(prev_shift.start_datetime.date(), relieving_date)
-				if relieving_date
-				else prev_shift.start_datetime.date()
-			)
-		else:
+		start_date, end_date = self.get_start_and_end_dates(employee)
+
+		# no shift assignment found, no need to process absent attendance records
+		if end_date is None:
 			return
+
 		holiday_list_name = self.holiday_list
 		if not holiday_list_name:
 			holiday_list_name = get_holiday_list_for_employee(employee, False)
-		dates = get_filtered_date_list(employee, start_date, end_date, holiday_list=holiday_list_name)
 
-		for date in dates:
-			shift_details = get_employee_shift(employee, get_datetime(date), True)
+		start_time = get_time(self.start_time)
+
+		for date in daterange(getdate(start_date), getdate(end_date)):
+			if is_holiday(holiday_list_name, date):
+				# skip marking absent on a holiday
+				continue
+
+			timestamp = datetime.combine(date, start_time)
+			shift_details = get_employee_shift(employee, timestamp, True)
+
 			if shift_details and shift_details.shift_type.name == self.name:
 				mark_attendance(employee, date, "Absent", self.name)
 
-	def get_assigned_employee(self, from_date=None, consider_default_shift=False):
-		filters = {"start_date": (">", from_date), "shift_type": self.name, "docstatus": "1"}
-		if not from_date:
-			del filters["start_date"]
+	def get_start_and_end_dates(self, employee):
+		date_of_joining, relieving_date, employee_creation = frappe.db.get_value("Employee", employee,
+			["date_of_joining", "relieving_date", "creation"])
 
-		assigned_employees = frappe.get_all("Shift Assignment", "employee", filters, as_list=True)
-		assigned_employees = [x[0] for x in assigned_employees]
+		if not date_of_joining:
+			date_of_joining = employee_creation.date()
+
+		start_date = max(getdate(self.process_attendance_after), date_of_joining)
+		end_date = None
+
+		shift_details = get_shift_details(self.name, get_datetime(self.last_sync_of_checkin))
+		last_shift_time = shift_details.actual_start if shift_details else get_datetime(self.last_sync_of_checkin)
+
+		prev_shift = get_employee_shift(employee, last_shift_time - timedelta(days=1), True, 'reverse')
+		if prev_shift:
+			end_date = min(prev_shift.start_datetime.date(), relieving_date) if relieving_date else prev_shift.start_datetime.date()
+
+		return start_date, end_date
+
+	def get_assigned_employee(self, from_date=None, consider_default_shift=False):
+		filters = {'shift_type': self.name, 'docstatus': '1'}
+		if from_date:
+			filters['start_date'] = ('>', from_date)
+
+		assigned_employees = frappe.get_all('Shift Assignment', filters=filters, pluck='employee')
 
 		if consider_default_shift:
-			filters = {"default_shift": self.name, "status": ["!=", "Inactive"]}
-			default_shift_employees = frappe.get_all("Employee", "name", filters, as_list=True)
-			default_shift_employees = [x[0] for x in default_shift_employees]
-			return list(set(assigned_employees + default_shift_employees))
+			filters = {'default_shift': self.name, 'status': ['!=', 'Inactive']}
+			default_shift_employees = frappe.get_all('Employee', filters=filters, pluck='name')
+
+			return list(set(assigned_employees+default_shift_employees))
 		return assigned_employees
 
 
@@ -138,42 +154,3 @@
 	for shift in shift_list:
 		doc = frappe.get_doc("Shift Type", shift[0])
 		doc.process_auto_attendance()
-
-
-def get_filtered_date_list(
-	employee, start_date, end_date, filter_attendance=True, holiday_list=None
-):
-	"""Returns a list of dates after removing the dates with attendance and holidays"""
-	base_dates_query = """select adddate(%(start_date)s, t2.i*100 + t1.i*10 + t0.i) selected_date from
-		(select 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t0,
-		(select 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t1,
-		(select 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t2"""
-	condition_query = ""
-	if filter_attendance:
-		condition_query += """ and a.selected_date not in (
-			select attendance_date from `tabAttendance`
-			where docstatus = 1 and employee = %(employee)s
-			and attendance_date between %(start_date)s and %(end_date)s)"""
-	if holiday_list:
-		condition_query += """ and a.selected_date not in (
-			select holiday_date from `tabHoliday` where parenttype = 'Holiday List' and
-    		parentfield = 'holidays' and parent = %(holiday_list)s
-    		and holiday_date between %(start_date)s and %(end_date)s)"""
-
-	dates = frappe.db.sql(
-		"""select * from
-		({base_dates_query}) as a
-		where a.selected_date <= %(end_date)s {condition_query}
-		""".format(
-			base_dates_query=base_dates_query, condition_query=condition_query
-		),
-		{
-			"employee": employee,
-			"start_date": start_date,
-			"end_date": end_date,
-			"holiday_list": holiday_list,
-		},
-		as_list=True,
-	)
-
-	return [getdate(date[0]) for date in dates]